<form [formGroup]="form">
  <mat-form-field>
    <mat-label>Label</mat-label>
    <input matInput formControlName="label" />
  </mat-form-field>
  <mat-form-field>
    <mat-label>Shape</mat-label>
    <mat-select formControlName="shape">
      <mat-option *ngFor="let shape of shapes" [value]="shape">
        {{ shape }}
      </mat-option>
    </mat-select>
  </mat-form-field>
</form>